Delineating the enhanced efficiency of carbon nanomaterials including the hierarchical architecture of the photoanode of dye-sensitized solar cells

Abstract

Dye-sensitized solar cells are economical and easy to fabricate in comparison to silicon-based solar cells. The visible light sensitizer dye is the main component of DSSCs, the performance of which can be enhanced if the TiO₂ semiconductor is engineered to maximize the utilization of the dye together with its easy regeneration from its oxidized form. In this study, a hierarchical porous architecture was imparted to the TiO₂ photoanode using size-selected (1.5 to 3 nm) carbon nanomaterials (CNMs). This porous structure enhanced the accessibility of the dye to the electrolyte. Using the N719 dye as a model system, the effect of the hierarchical porous structure was demonstrated. The inclusion of CNMs together with TiO₂ enhanced the short circuit current density by 31% and power conversion efficiency (PCE) by 46% compared to the CNM-free DSSCs.